Handle errors in describe blocks
Handle errors in describe blocks

Fixes part of #260

Also, cc @kbambz :P
ryanplusplus/busted,nehz/busted,o-lim/busted,sobrinho/busted,xyliuke/busted,istr/busted,DorianGray/busted,Olivine-Labs/busted,mpeterv/busted,leafo/busted